1. Field of the Invention
The present invention relates to printing devices, and in particular, to a handheld portable printer and a method of operation.
2. Description of the Background Art
Printers are well known in the art and there are a variety of different types such as laser printers, dot-matrix printers and ink jet printers. Each of these printers uses a different type of technology for applying the “ink” to the print media (“paper”). However, most all printers require that the print media be moved past a relatively stationary print head that applies the “ink” to the print media. Most often such printers have a housing for holding the print head in a fixed orientation and complex paper handling trays and mechanisms to feed the print media past the print head and render the printed output. Since most printers require such a large housing, such printers are not hand held, but rather large devices significantly greater in size than a standard sheet of 8×11″ sheet of paper. While there have been some printers created for a mobile computing environment, such printers often have a print head or print head mechanism that is at least 8.5 inches in length.
There have been attempts in the prior art to provide a hand held printer. These attempts include a typical approach of reducing the size of the print head so that it can be mounted within a portable housing along with electronics, the power supply and other elements of a printer. However, existing hand-held printers have significant limitations. For many existing hand-held printers, the size of the image that they are able to print is severely limited. For example, some prior art printers are able to print only while they are stationary, and thus, are limited to printing images less than or equal to the printer itself or the print head, which in either case is less that a few inches square. This also makes the printer bulky and difficult to use.
Other handheld printers allow printing while the user moves or “swipes” the handheld printer across or over the print media. However, these printers are again limited in at least one dimension in the size of the images they are able to print. Specifically, they are only able to print an image less than or equal to the size of the print head, and most are limited to one pass or swipe. For those handheld printers that are able to print in sections, it is very difficult to align the multiple, separate printing steps, swipes or sections. Moreover, some printers allow images to be printed in multiple sections require special paper, registration marks or require starting printing at an edge boundary. Furthermore, there is a high misprinting or failure rate with such multiple section hand-held printers. For example, failure to print the image properly often occurs if the user prematurely removes the printing device from the surface of the print medium.
Therefore, what are needed are a handheld portable printer and a method of operation that are easier to use, and are capable of printing images on surfaces regardless of the size of the printed image.